Electrochemotherapy (ECT) is a local treatment of cancer, which combines the use of a medical device with pharmaceutical agents to achieve local tumour control in solid cancers. The procedure consists of applying short high-intensity pulsed electric fields to cells, in response to which the plasma membrane's permeability to various molecules transiently increases. This facilitates cellular uptake of cytotoxic agents, thus increasing their cytotoxicity. The treatment is based on electroporation, which occurs when an externally delivered electric field induces a sufficiently large transmembrane voltage. Electroporation is, in addition to its use in electrochemotherapy, used also as non-viral gene delivery method to cells in vitro and in vivo—gene electrotransfer. Furthermore, electroporation as sole modality can be used as tumour ablation in the form of irreversible electroporation, also referred to as non-thermal irreversible electroporation.
Applications for electrochemotherapeutic-based treatment of cutaneous and subcutaneous tumours using drugs such as bleomycin and cisplatin have reached clinical use. ECT with bleomycin was used to treat a patient for the first time in 1991, while ECT with cisplatin was used for the first time in 1995. Multiple positioning of the electrodes, and subsequent pulse delivery, can be performed during a session to treat the whole lesion, provided that drug concentration is sufficient. Treatment can be repeated over the course of weeks or months to achieve regression of large lesions.
In a number of clinical studies (phase II and phase III), investigators have concluded that ECT of cutaneous or subcutaneous metastasis or tumours with bleomycin and cisplatin have an objective response rate of more than 80%. Reduction of tumour size has been achieved with electrochemotherapy faster and more efficiently than in standard chemotherapy for both cutaneous and subcutaneous tumours.
Whilst studies have shown that ECT is effective at achieving local tumour reduction and potential tumour resolution, it is largely incapable of generating a systemic antigen specific T/B cell immune response. This incapability can lead to disease reoccurrence.
There is thus a need for a cancer therapy, which is not associated with these issues.